/*
   Copyright 2007 Marco Slot (marco.slot@gmail.com)

   Licensed under the Apache License, Version 2.0 (the "License");
   you may not use this file except in compliance with the License.
   You may obtain a copy of the License at

       http://www.apache.org/licenses/LICENSE-2.0

   Unless required by applicable law or agreed to in writing, software
   distributed under the License is distributed on an "AS IS" BASIS,
   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   See the License for the specific language governing permissions and
   limitations under the License.
 */
package nl.marcoslot.lib.calc;

/**
 * This interface is used for classes with a value.
 * Objects with type Value can be added to an Expression.
 *
 * @author Marco Slot
 */
public interface Value {
    /**
     * Returns the value of the object
     * 
     * @return 
     *    the value of the object
     */
   double value();
}
